There's nothing like a world television first to get the adrenal glands pumping: John Logie Baird's 1926 demonstration at the Royal Institution in London; the first colour broadcasts in the US in 1953; and some Twitter activity around the latest ad for the new Alien film during an episode of Homeland on Channel 4 last night.

Twentieth Century Fox's move to screen reactions to the latest trailer for Prometheus, which was shown during the show's first commercial break, is just the latest marketing gimmick for Ridley Scott's return to science fiction after more than three decades. Earlier this year, Fox began screening short teaser promos for the film's debut trailer, and there have also been extensive viral videos and screenshots to whet our appetites. It's as if Fox saw the success of The Dark Knight's promotional campaign in 2008 and decided to quadruple the marketing spend. Never mind being consumed by xenomorphs, Prometheus is in serious danger of eating itself.

So far, the creative team behind the campaign has managed to juggle avaricious appetites for snippets of information with the need to keep the twists and turns of the movie under wraps, but I wonder whether it's let a little too much slip in the new trailer. Ever since Scott decided that Prometheus was a film "set in the universe" of the original Alien movies, rather than a full-blown prequel, the whole world has been trying to work out exactly what the connection is. The veteran British film-maker says the secret will be revealed only in the last 10 minutes of the film, in which case what on Earth are all those suspiciously xenomorph-like creatures doing in the new trailer?

The promo shows us what appear to be proto-facehuggers, a shot of something that resembles a xenomorph standing tall and at least five or six more images of horrible nasty things apparently doing horrible nasty stuff to the poor crew of the Prometheus. Or does it? Is this all just a case of smoke and mirrors? Because if not, I'm starting to think I can predict the entire film's storyline before I've even seen it.

The Twitter stunt certainly seems to have boosted hype surrounding the film to an even more intense level than before: the hashtag #areyouseeingthis was the No 2 trend in the UK at one point on Sunday night, and a similar campaign has been under way in the US. But are we all now seeing rather too much of what had previously been a deliciously enigmatic project? Do you long for the days when Prometheus was just a twinkle in Scott's eye, or are you yearning for more trailers for trailers and perhaps a gallery of shots from every key scene from the film including the ending? Now that would be a world first.

The director and star of the highly anticipated Alien origins story tell Paul MacInnes about extra terrestrials, the danger in searching for answers to life's big questions and how much Scott's 1979 sci-fi horror classic has influenced his new film